Milliwatt (SI symbol: mW) is a unit for measuring electrical power, equal to one-thousandth (10^-3) of a watt.

See also: Orders of magnitude (power)

microwatt << milliwatt >> watt

Milliwatt is also a telecommunications tone. It is a 1004 hz tone, used for testing purposes. When you call a milliwatt number, you simply hear this tone. For an example, call 1-800-485-9076 or 1-877-250-0600 . These are toll-free WATS numbers. Most milliwatts are not toll-free, however.